CHAPTER 20

SMOKE MACHINES

Smoke is used to create many effects. The smoke provides a medium for the beams of light so that the beams can be seen rather than just illuminating the stage floor. All smoke machines become hot as part of the process of making the smoke and must be handled very carefully.

FOGGERS  

Fog machines use water- or oil-based fluids to produce a vapor that looks like puffy smoke and is spread across the stage with fans. Because fluid vaporization is never complete, a residue eventually builds up and must be cleaned regularly to maintain optimum machine performance. Place the fog machine so that the area in front of it is clear enough for the vapor to dissipate.

DRY ICE MACHINES  

The difference between dry ice and fog is that dry ice vapor falls to the floor whereas fog rises. Dry ice machines are like big kettles that heat water. The ice is lowered into the boiling water to produce vapor, which looks like smoke. Fans and flexible tubing are needed to move the vapor to where it is needed.

Dry ice burns the skin; wear gloves when handling it. The ice comes in blocks or pellets, and the blocks must be broken up so that the ice is evenly distributed in the machine. Do not let the machine boil dry. Turn the machine off when it is not in use. Remember to allow time for the water to boil before the smoke effect is needed.

PYROTECHNICS  

The term pyrotechnics refers to any flash or bang. Many stage fireworks are available. Because fireworks are dangerous, the operator must be licensed.

CRACKED OIL  

Cracked-oil smoke is made by exposing a fine oil to compressed air. The air compressor is connected to outlet tanks that contain the oil. The compressed air is fed into the oil through a collection of spray jets. A fine mist results.